Semiconductor device and method of embedding integrated passive devices into the package electrically interconnected using conductive pillars

ABSTRACT

A semiconductor device has a first insulation layer formed over a sacrificial substrate. A first conductive layer is formed over the first insulating layer. Conductive pillars are formed over the first conductive layer. A pre-fabricated IPD is disposed between the conductive pillars. An encapsulant is formed around the IPD and conductive pillars. A second insulation layer is formed over the encapsulant. The conductive pillars are electrically connected to the first and second conductive layers. The first and second conductive layers each include an inductor. Semiconductor devices are mounted over the first and second insulating layer and electrically connected to the first and second conductive layers, respectively. An interconnect structure is formed over the first and second insulating layers, respectively, and electrically connected to the first and second conductive layers. The sacrificial substrate is removed. The semiconductor devices can be stacked and electrically interconnected through the conductive pillars.

FIELD OF THE INVENTION

The present invention relates in general to semiconductor devices and,more particularly, to a semiconductor device having an embeddedintegrated passive device which is electrically interconnected on asemiconductor package using conductive pillars.

BACKGROUND OF THE INVENTION

Semiconductor devices are commonly found in modern electronic products.Semiconductor devices vary in the number and density of electricalcomponents. Discrete semiconductor devices generally contain one type ofelectrical component, e.g., light emitting diode (LED), transistor,resistor, capacitor, inductor, and power metal oxide semiconductor fieldeffect transistor (MOSFET). Integrated semiconductor devices typicallycontain hundreds to millions of electrical components. Examples ofintegrated semiconductor devices include microcontrollers,microprocessors, charged-coupled devices (CCDs), solar cells, anddigital micro-mirror devices (DMDs).

Semiconductor devices perform a wide range of functions such ashigh-speed calculations, transmitting and receiving electromagneticsignals, controlling electronic devices, transforming sunlight toelectricity, and creating visual projections for television displays.Semiconductor devices are found in the fields of entertainment,communications, power generation, networks, computers, and consumerproducts. Semiconductor devices are also found in electronic productsincluding military, aviation, automotive, industrial controllers, andoffice equipment.

Semiconductor devices exploit the electrical properties of semiconductormaterials. The atomic structure of semiconductor material allows itselectrical conductivity to be manipulated by the application of anelectric field or through the process of doping. Doping introducesimpurities into the semiconductor material to manipulate and control theconductivity of the semiconductor device.

A semiconductor device contains active and passive electricalstructures. Active structures, including transistors, control the flowof electrical current. By varying levels of doping and application of anelectric field, the transistor either promotes or restricts the flow ofelectrical current. Passive structures, including resistors, diodes, andinductors, create a relationship between voltage and current necessaryto perform a variety of electrical functions. The passive and activestructures are electrically connected to form logic circuits, whichenable the semiconductor device to perform high-speed calculations andother useful functions.

Semiconductor devices are generally manufactured using two complexmanufacturing processes, i.e., front-end manufacturing, and back-endmanufacturing, each involving potentially hundreds of steps. Front-endmanufacturing involves the formation of a plurality of die on thesurface of a semiconductor wafer. Each die is typically identical andcontains circuits formed by electrically connecting active and passivecomponents. Back-end manufacturing involves singulating individual diefrom the finished wafer and packaging the die to provide structuralsupport and environmental isolation.

One goal of semiconductor manufacturing is to produce smallersemiconductor devices. Smaller devices typically consume less power,have higher performance, and can be produced more efficiently. Inaddition, smaller semiconductor devices have a smaller footprint, whichis desirable for smaller end products. A smaller die size may beachieved by improvements in the front-end process resulting in die withsmaller, higher density active and passive components. Back-endprocesses may result in semiconductor device packages with a smallerfootprint by improvements in electrical interconnection and packagingmaterials.

Another goal of semiconductor manufacturing is to produce higherperformance semiconductor devices. Increases in device performance canbe accomplished by forming active components that are capable ofoperating at higher speeds. In high frequency applications, such asradio frequency (RF) wireless communications, integrated passive devices(IPDs) are often contained within the semiconductor device. Examples ofIPDs include resistors, capacitors, and inductors. A typical RF systemrequires multiple IPDs in one or more semiconductor packages to performthe necessary electrical functions. However, high frequency electricaldevices generate or are susceptible to undesired electromagneticinterference (EMI) and radio frequency interference (RFI), or otherinter-device interference, such as capacitive, inductive, or conductivecoupling, also known as cross-talk.

In many applications, semiconductor devices combine analog and digitalcircuitry. Semiconductor devices use one or more inductors andcapacitors to implement the device's RF components and to provide systemfunctionality. In some packages, the inductors and capacitors areprovided as part of a pre-fabricated IPD that is mounted to thesemiconductor device and electrically connected to other components ofthe semiconductor device. The interconnection between the active andpassive devices is typically accomplished using conductive throughsilicon vias (TSV). TSVs provide electrical interconnection pathsvertically through the semiconductor device. However, the use of TSVsadds manufacturing cost and complicates device integration, particularlyfor thick wafers. In addition, TSV-type semiconductor packages oftenlack sufficient EMI protection.

SUMMARY OF THE INVENTION

A need exists to electrically interconnect pre-fabricated IPDs withother active and passive devices in the semiconductor package.Accordingly, in one embodiment, the present invention is a method ofmanufacturing a semiconductor device comprising the steps of providing apre-fabricated integrated passive device (IPD), providing a sacrificialsubstrate, forming a first insulation layer over the sacrificialsubstrate, forming a first conductive layer over the first insulatinglayer, forming a plurality of conductive pillars over the firstconductive layer, attaching the IPD to the first conductive layerbetween the conductive pillars, forming an encapsulant around the IPDand conductive pillars, forming a second insulation layer over theencapsulant, and forming a second conductive layer over the secondinsulating layer. The second conductive layer is electrically connectedto the conductive pillars. The method further includes the step ofremoving the sacrificial substrate.

In another embodiment, the present invention is a method ofmanufacturing a semiconductor device comprising the steps of providing atemporary substrate, forming a first conductive layer over the temporarycarrier, forming a plurality of conductive pillars over the firstconductive layer, attaching an IPD to the first conductive layer betweenthe conductive pillars, forming an encapsulant around the IPD andconductive pillars, forming a first insulation layer over theencapsulant and conductive pillars, and forming a second conductivelayer over the first insulating layer. The second conductive layer iselectrically connected to the conductive pillars. The method furtherincludes the step of removing the sacrificial substrate.

In another embodiment, the present invention is a method ofmanufacturing a semiconductor device comprising the steps of providing afirst interconnect structure, and forming a plurality of conductivepillars over the first interconnect structure. The conductive pillarsare electrically connected to the first interconnect structure. Themethod further includes the steps of attaching an IPD to the firstinterconnect structure between the conductive pillars, and forming anencapsulant around the IPD and conductive pillars.

In another embodiment, the present invention is a semiconductor devicecomprising a first interconnect structure, and plurality of conductivepillars formed over the first interconnect structure. The conductivepillars are electrically connected to the first interconnect structure.An IPD is disposed between the conductive pillars. An encapsulant isformed around the IPD and conductive pillars.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a PCB with different types of packages mounted to itssurface;

FIGS. 2 a-2 d illustrates further detail of the semiconductor packagesmounted to the PCB;

FIGS. 3 a-3 b illustrate pre-fabrication of an IPD structure;

FIGS. 4 a-4 e illustrate a process of forming conductive pillars toelectrically interconnect the pre-fabricated IPD;

FIG. 5 illustrates the IPD electrically interconnected using conductivepillars;

FIG. 6 illustrates another embodiment of the IPD electricallyinterconnected using conductive pillars;

FIG. 7 illustrates another embodiment of the IPD electricallyinterconnected using conductive pillars;

FIG. 8 illustrates stacked semiconductor devices;

FIG. 9 illustrates the IPD electrically interconnected using conductivepillars with additional front-side semiconductor die or component;

FIG. 10 illustrates the IPD electrically interconnected using conductivepillars with an inductor formed in the conductive layers; and

FIG. 11 illustrates the IPD electrically interconnected using conductivepillars with a front-side external interconnect structure.

DETAILED DESCRIPTION OF THE DRAWINGS

The present invention is described in one or more embodiments in thefollowing description with reference to the Figures, in which likenumerals represent the same or similar elements. While the invention isdescribed in terms of the best mode for achieving the invention'sobjectives, it will be appreciated by those skilled in the art that itis intended to cover alternatives, modifications, and equivalents as maybe included within the spirit and scope of the invention as defined bythe appended claims and their equivalents as supported by the followingdisclosure and drawings.

Semiconductor devices are generally manufactured using two complexmanufacturing processes: front-end manufacturing and back-endmanufacturing. Front-end manufacturing involves the formation of aplurality of die on the surface of a semiconductor wafer. Each die onthe wafer contains active and passive electrical components, which areelectrically connected to form functional electrical circuits. Activeelectrical components, such as transistors, have the ability to controlthe flow of electrical current. Passive electrical components, such ascapacitors, inductors, resistors, and transformers, create arelationship between voltage and current necessary to perform electricalcircuit functions.

Passive and active components are formed on the surface of thesemiconductor wafer by a series of process steps including doping,deposition, photolithography, etching, and planarization. Dopingintroduces impurities into the semiconductor material by techniques suchas ion implantation or thermal diffusion. The doping process modifiesthe electrical conductivity of semiconductor material in active devices,transforming the semiconductor material into a permanent insulator,permanent conductor, or changing the way the semiconductor materialchanges in conductivity in response to an electric field. Transistorscontain regions of varying types and degrees of doping arranged asnecessary to enable the transistor to promote or restrict the flow ofelectrical current upon the application of an electric field.

Active and passive components are formed by layers of materials withdifferent electrical properties. The layers can be formed by a varietyof deposition techniques determined in part by the type of materialbeing deposited. For example, thin film deposition may involve chemicalvapor deposition (CVD), physical vapor deposition (PVD), electrolyticplating, and electroless plating processes. Each layer is generallypatterned to form portions of active components, passive components, orelectrical connections between components.

The layers can be patterned using photolithography, which involves thedeposition of light sensitive material, e.g., photoresist, over thelayer to be patterned. A pattern is transferred from a photomask to thephotoresist using light. The portion of the photoresist patternsubjected to light is removed using a solvent, exposing portions of theunderlying layer to be patterned. The remainder of the photoresist isremoved, leaving behind a patterned layer. Alternatively, some types ofmaterials are patterned by directly depositing the material into theareas or voids formed by a previous deposition/etch process usingtechniques such as electroless and electrolytic plating.

Depositing a thin film of material over an existing pattern canexaggerate the underlying pattern and create a non-uniformly flatsurface. A uniformly flat surface is required to produce smaller andmore densely packed active and passive components. Planarization can beused to remove material from the surface of the wafer and produce auniformly flat surface. Planarization involves polishing the surface ofthe wafer with a polishing pad. An abrasive material and corrosivechemical are added to the surface of the wafer during polishing. Thecombined mechanical action of the abrasive and corrosive action of thechemical removes any irregular topography, resulting in a uniformly flatsurface.

Back-end manufacturing refers to cutting or singulating the finishedwafer into the individual die and then packaging the die for structuralsupport and environmental isolation. To singulate the die, the wafer isscored and broken along non-functional regions of the wafer called sawstreets or scribes. The wafer is singulated using a laser cutting deviceor saw blade. After singulation, the individual die are mounted to apackage substrate that includes pins or contact pads for interconnectionwith other system components. Contact pads formed over the semiconductordie are then connected to contact pads within the package. Theelectrical connections can be made with solder bumps, stud bumps,conductive paste, or wirebonds. An encapsulant or other molding materialis deposited over the package to provide physical support and electricalisolation. The finished package is then inserted into an electricalsystem and the functionality of the semiconductor device is madeavailable to the other system components.

FIG. 1 illustrates electronic device 10 having a chip carrier substrateor printed circuit board (PCB) 12 with a plurality of semiconductorpackages mounted on its surface. Electronic device 10 may have one typeof semiconductor package, or multiple types of semiconductor packages,depending on the application. The different types of semiconductorpackages are shown in FIG. 1 for purposes of illustration.

Electronic device 10 may be a stand-alone system that uses thesemiconductor packages to perform an electrical function. Alternatively,electronic device 10 may be a subcomponent of a larger system. Forexample, electronic device 10 may be a graphics card, network interfacecard, or other signal processing card that can be inserted into acomputer. The semiconductor package can include microprocessors,memories, application specific integrated circuits (ASICs), logiccircuits, analog circuits, RF circuits, discrete devices, or othersemiconductor die or electrical components.

In FIG. 1, PCB 12 provides a general substrate for structural supportand electrical interconnect of the semiconductor packages mounted on thePCB. Conductive signal traces 14 are formed on a surface or withinlayers of PCB 12 using evaporation, electrolytic plating, electrolessplating, screen printing, PVD, or other suitable metal depositionprocess. Signal traces 14 provide for electrical communication betweeneach of the semiconductor packages, mounted components, and otherexternal system components. Traces 14 also provide power and groundconnections to each of the semiconductor packages.

In some embodiments, a semiconductor device has two packaging levels.First level packaging is a technique for mechanically and electricallyattaching the semiconductor die to a carrier. Second level packaginginvolves mechanically and electrically attaching the carrier to the PCB.In other embodiments, a semiconductor device may only have the firstlevel packaging where the die is mechanically and electrically mounteddirectly to the PCB.

For the purpose of illustration, several types of first level packaging,including wire bond package 16 and flip chip 18, are shown on PCB 12.Additionally, several types of second level packaging, including ballgrid array (BGA) 20, bump chip carrier (BCC) 22, dual in-line package(DIP) 24, land grid array (LGA) 26, multi-chip module (MCM) 28, quadflat non-leaded package (QFN) 30, and quad flat package 32, are shownmounted on PCB 12. Depending upon the system requirements, anycombination of semiconductor packages, configured with any combinationof first and second level packaging styles, as well as other electroniccomponents, can be connected to PCB 12. In some embodiments, electronicdevice 10 includes a single attached semiconductor package, while otherembodiments call for multiple interconnected packages. By combining oneor more semiconductor packages over a single substrate, manufacturerscan incorporate pre-made components into electronic devices and systems.Because the semiconductor packages include sophisticated functionality,electronic devices can be manufactured using cheaper components and ashorter manufacturing process. The resulting devices are less likely tofail and less expensive to manufacture resulting in lower costs forconsumers.

FIG. 2 a illustrates further detail of DIP 24 mounted on PCB 12. DIP 24includes semiconductor die 34 having contact pads 36. Semiconductor die34 includes an active region containing analog or digital circuitsimplemented as active devices, passive devices, conductive layers, anddielectric layers formed within semiconductor die 34 and areelectrically interconnected according to the electrical design of thedie. For example, the circuit may include one or more transistors,diodes, inductors, capacitors, resistors, and other circuit elementsformed within the active region of die 34. Contact pads 36 are made witha conductive material, such as aluminum (Al), copper (Cu), tin (Sn),nickel (Ni), gold (Au), or silver (Ag), and are electrically connectedto the circuit elements formed within die 34. Contact pads 36 are formedby PVD, CVD, electrolytic plating, or electroless plating process.During assembly of DIP 24, semiconductor die 34 is mounted to a carrier38 using a gold-silicon eutectic layer or adhesive material such asthermal epoxy. The package body includes an insulative packagingmaterial such as polymer or ceramic. Conductor leads 40 are connected tocarrier 38 and wire bonds 42 are formed between leads 40 and contactpads 36 of die 34 as a first level packaging. Encapsulant 44 isdeposited over the package for environmental protection by preventingmoisture and particles from entering the package and contaminating die34, contact pads 36, or wire bonds 42. DIP 24 is connected to PCB 12 byinserting leads 40 into holes formed through PCB 12. Solder material 46is flowed around leads 40 and into the holes to physically andelectrically connect DIP 24 to PCB 12. Solder material 46 can be anymetal or electrically conductive material, e.g., Sn, lead (Pb), Au, Ag,Cu, zinc (Zn), bismuthinite (Bi), and alloys thereof, with an optionalflux material. For example, the solder material can be eutectic Sn/Pb,high-lead, or lead-free.

FIG. 2 b illustrates further detail of BCC 22 mounted on PCB 12.Semiconductor die 47 is connected to a carrier by wire bond style firstlevel packaging. BCC 22 is mounted to PCB 12 with a BCC style secondlevel packaging. Semiconductor die 47 having contact pads 48 is mountedover a carrier using an underfill or epoxy-resin adhesive material 50.Semiconductor die 47 includes an active region containing analog ordigital circuits implemented as active devices, passive devices,conductive layers, and dielectric layers formed within semiconductor die47 and are electrically interconnected according to the electricaldesign of the die. For example, the circuit may include one or moretransistors, diodes, inductors, capacitors, resistors, and other circuitelements formed within the active region of die 47. Contact pads 48 aremade with a conductive material, such as Al, Cu, Sn, Ni, Au, or Ag, andare electrically connected to the circuit elements formed within die 47.Contact pads 48 are formed by PVD, CVD, electrolytic plating, orelectroless plating process. Wire bonds 54 and bond pads 56 and 58electrically connect contact pads 48 of semiconductor die 47 to contactpads 52 of BCC 22 forming the first level packaging. Molding compound orencapsulant 60 is deposited over semiconductor die 47, wire bonds 54,contact pads 48, and contact pads 52 to provide physical support andelectrical isolation for the device. Contact pads 64 are formed on asurface of PCB 12 using evaporation, electrolytic plating, electrolessplating, screen printing, PVD, or other suitable metal depositionprocess and are typically plated to prevent oxidation. Contact pads 64electrically connect to one or more conductive signal traces 14. Soldermaterial is deposited between contact pads 52 of BCC 22 and contact pads64 of PCB 12. The solder material is reflowed to form bumps 66 whichform a mechanical and electrical connection between BCC 22 and PCB 12.

In FIG. 2 c, semiconductor die 18 is mounted face down to carrier 76with a flip chip style first level packaging. BGA 20 is attached to PCB12 with a BGA style second level packaging. Active region 70 containinganalog or digital circuits implemented as active devices, passivedevices, conductive layers, and dielectric layers formed withinsemiconductor die 18 is electrically interconnected according to theelectrical design of the die. For example, the circuit may include oneor more transistors, diodes, inductors, capacitors, resistors, and othercircuit elements formed within active region 70 of semiconductor die 18.Semiconductor die 18 is electrically and mechanically attached tocarrier 76 through a large number of individual conductive solder bumpsor balls 78. Solder bumps 78 are formed on bump pads or interconnectsites 80, which are disposed on active region 70. Bump pads 80 are madewith a conductive material, such as Al, Cu, Sn, Ni, Au, or Ag, and areelectrically connected to the circuit elements formed in active region70. Bump pads 80 are formed by PVD, CVD, electrolytic plating, orelectroless plating process. Solder bumps 78 are electrically andmechanically connected to contact pads or interconnect sites 82 oncarrier 76 by a solder reflow process.

BGA 20 is electrically and mechanically attached to PCB 12 by a largenumber of individual conductive solder bumps or balls 86. The solderbumps are formed on bump pads or interconnect sites 84. The bump pads 84are electrically connected to interconnect sites 82 through conductivelines 90 routed through carrier 76. Contact pads 88 are formed on asurface of PCB 12 using evaporation, electrolytic plating, electrolessplating, screen printing, PVD, or other suitable metal depositionprocess and are typically plated to prevent oxidation. Contact pads 88electrically connect to one or more conductive signal traces 14. Thesolder bumps 86 are electrically and mechanically connected to contactpads or bonding pads 88 on PCB 12 by a solder reflow process. Moldingcompound or encapsulant 92 is deposited over semiconductor die 18 andcarrier 76 to provide physical support and electrical isolation for thedevice. The flip chip semiconductor device provides a short electricalconduction path from the active devices on semiconductor die 18 toconduction tracks on PCB 12 in order to reduce signal propagationdistance, lower capacitance, and achieve overall better circuitperformance. In another embodiment, the semiconductor die 18 can bemechanically and electrically attached directly to PCB 12 using flipchip style first level packaging without carrier 76.

FIGS. 3 a-3 b illustrate a process of forming a prefabricated integratedpassive device (IPD). In particular, FIG. 3 a shows pre-fabrication ofan IPD formed over a high-resistivity substrate. An insulating layer 102is formed on substrate 104. Substrate 104 is made with a highresistivity silicon, glass, or other similar material. The insulatinglayer 102 can be silicon dioxide (SiO2), silicon nitride (Si3N4),silicon oxynitride (SiON), tantalum pentoxide (Ta2O5), zircon (ZrO2),aluminum oxide (Al2O3), or other material having suitable insulatingproperties. The insulating layer 102 is patterned or blanket depositedusing PVD, CVD, printing, sintering, or thermal oxidation. Theinsulating layer 102 can be single or multiple layers.

An electrically conductive layer 106 is patterned and deposited overinsulating layer 102 to form individual portions or sections 106 a-106c. The individual portions of conductive layer 106 can be electricallycommon or electrically isolated depending on the connectivity of theindividual semiconductor die formed on wafer 100. Conductive layer 106can be Al, Cu, Sn, Ni, Au, Ag, or other suitable electrically conductivematerial. The deposition of conductive layer 106 uses PVD, CVD,electrolytic plating, or electroless plating process.

A resistive layer 108 is patterned and deposited on insulating layer 102and conductive layer 106 using PVD or CVD. Resistive layer 108 hasindividual portions or sections 108 a-108 b. Resistive layer 108 a isdeposited over insulating layer 102 between conductive layers 106 a-106b. Resistive layer 108 b is deposited over conductive layer 106 b. Theindividual portions of resistive layer 108 can be electrically connectedor electrically isolated depending on the connectivity of the individualsemiconductor die formed on wafer 100. Resistive layer 108 is tantalumsilicide (TaxSiy) or other metal silicides, TaN, nickel chromium (NiCr),TiN, or doped poly-silicon having a resistivity between 5 and 100ohm/sq.

An insulating layer 110 is formed over resistive layer 108 b. Theinsulating layer 110 can be Si3N4, SiO2, SiON, Ta2O5, ZnO, ZrO2, Al2O3,or other suitable dielectric material. The insulating layer 110 ispatterned or blanket deposited using PVD, CVD, printing, sintering, orthermal oxidation. Resistive layer 108 and insulating layer 110 areformed with the same mask and etched at the same time. Alternatively,resistive layer 108 and insulating layer 110 can be patterned and etchedwith a different mask.

An insulating or passivation layer 112 is formed over insulating layer102, conductive layer 106, resistive layer 108 a, and insulating layer110. The passivation layer 112 can be SiO2, Si3N4, SiON, Ta2O5, Al2O3,polyimide, benzocyclobutene (BCB), polybenzoxazoles (PBO), or othermaterial having suitable insulating properties. The deposition ofpassivation layer 112 may involve spin coating, PVD, CVD, printing,sintering, or thermal oxidation. A portion of passivation layer 112 isremoved to expose conductive layer 106 a-106 c, insulating layer 110,and resistive layer 108 a.

An electrically conductive layer 114 is patterned and deposited overconductive layer 106 a-106 c, insulating layer 110, resistive layer 108a, and passivation layer 112 to form individual portions or sections 114a-114 i. The individual portions of conductive layer 114 can beelectrically common or electrically isolated depending on theconnectivity of the individual semiconductor die formed on wafer 100.Conductive layer 114 can be Al, Cu, Sn, Ni, Au, Ag, or other suitableelectrically conductive material. The deposition of conductive layer 114uses PVD, CVD, electrolytic plating, or electroless plating process.

An insulating layer 116 is formed over passivation layer 112 andconductive layer 114. The insulating layer 116 can be SiO2, Si3N4, SiON,Ta2O5, Al2O3, or other material having suitable insulating properties.The deposition of insulating layer 116 may involve spin coating, PVD,CVD, printing, sintering, or thermal oxidation. A portion of insulatinglayer 116 is removed to expose conductive layers 114 a, 114 c, and 114i.

An electrically conductive solder material is deposited over conductivelayer 114 a, 114 c, and 114 i using an evaporation, electrolyticplating, electroless plating, ball drop, or screen printing process. Thesolder material can be any metal or other electrically conductivematerial, e.g., Sn, Ni, Au, Ag, Pb, Bi, and alloys thereof, with anoptional flux material. For example, the solder material can be eutecticSn/Pb, high-lead, or lead-free. The solder material is reflowed byheating the material above its melting point to form spherical balls orbumps 118. In some applications, solder bumps 118 are reflowed a secondtime to improve electrical contact to conductive layer 114. Solder bumps118 represent one type of interconnect structure that can be formed onconductive layer 114. The interconnect structure can also use bondwires, 3D interconnects, conductive paste, or other electricalinterconnect.

The semiconductor wafer 100 is singulated with saw blade or laser toolinto individual IPD structures 121, each with a high resistivitysubstrate 104. The structures described in FIG. 3 a, e.g., thecombination of conductive layer 106, resistive layer 108, insulatinglayer 110, and conductive layer 114, constitute one or more passivecircuit elements or IPDs. In one embodiment, conductive layer 106 b,resistive layer 108 b, insulating layer 110, and conductive layer 114 bis a metal-insulator-metal (MIM) capacitor. Resistive layer 108 a is aresistor element in the passive circuit. The conductive layers 114 d-114h constitute an inductor. The conductive layers 114 d-114 h aretypically wound or coiled in plan-view to produce or exhibit the desiredinductive properties.

The pre-fabricated IPD structure 121 provides electrical characteristicsneeded for high frequency applications, such as resonators, high-passfilters, low-pass filters, band-pass filters, symmetric Hi-Q resonanttransformers, matching networks, and tuning capacitors. The IPDs can beused as front-end wireless RF components, which can be positionedbetween the antenna and transceiver. The IPD inductor can be a hi-Qbalun, transformer, or coil, operating up to 100 Gigahertz. In someapplications, multiple baluns are formed on a same substrate, allowingmulti-band operation. For example, two or more baluns are used in aquad-band for mobile phones or other global system for mobile (GSM)communications, each balun dedicated for a frequency band of operationof the quad-band device. A typical RF system requires multiple IPDs andother high frequency circuits in one or more semiconductor packages toperform the necessary electrical functions. However, high frequencyelectrical devices generate or are susceptible to undesiredelectromagnetic interference (EMI), radio frequency interference (RFI),or other inter-device interference, such as capacitive, inductive, orconductive coupling, also known as cross-talk.

FIG. 3 b shows an embodiment with adhesive layer 120 formed overinsulating layer 116 and contacting conductive layer 114 a, 114 c, and114 i. The adhesive layer 120 provides for later attachment ofsemiconductor layers or electrical components.

FIGS. 4 a-4 e illustrate a process of forming a semiconductor packagehaving an embedded IPD structure electrically interconnected on thepackage using conductive pillars. In particular, FIG. 4 a shows a firstpassivation layer 124 formed on substrate or carrier 122. Carrier 122 isa temporary or sacrificial base material such as silicon, ceramic,glass, or other suitable low-cost, rigid material. Passivation layer 124can be SiO2, Si3N4, SiON, Ta2O5, ZrO2, Al2O3, polyimide, BCB, PBO, orother material having suitable insulating properties. Passivation layer124 is patterned or blanket deposited using PVD, CVD, printing, spincoating, sintering, or thermal oxidation. Passivation layer 124 isoptional, provides stress relief, and operates as an etch stop.

A second passivation layer 126 is formed on passivation layer 124.Passivation layer 126 can be SiO2, Si3N4, SiON, Ta2O5, ZrO2, Al2O3,polyimide, BCB, PBO, or other material having suitable insulatingproperties. Passivation layer 126 is patterned or blanket depositedusing PVD, CVD, printing, spin coating, sintering, or thermal oxidation.Passivation layers 124 and 126 can be formed as one passivation layer. Aportion of passivation layer 126 is removed to form vias 128.

An electrically conductive layer 130 is patterned and deposited overpassivation layers 124 and 126 to form individual portions or sections130 a-130 e. The individual portions of conductive layer 130 can beelectrically common or electrically isolated depending on theconnectivity of the individual semiconductor die formed on carrier 122.Accordingly, conductive layer 130 constitutes an interconnect structure.

Further detail of via 128 in passivation layer 126 is shown in FIG. 4 b.Via 128 is filled with an adhesive layer 132. A barrier layer 134 isformed over adhesive layer 132. Conductive layer 130 is formed overbarrier layer 134. In another embodiment shown in FIG. 4 c, via 128 isfilled with an adhesive layer 132. A barrier layer 134 is formed overadhesive layer 132. Barrier layer 134 is optional. A seed layer 136 isformed over barrier layer 134. Conductive layer 130 is formed over seedlayer 136. In one embodiment, conductive layer 130 is stacked Ti/NiV/Cuor Al/NiV/Cu with Ti or AL as an adhesive layer, nickel vanadium (NiV)as a barrier layer, and Cu as a seed layer. Alternately, conductivelayer 130 can be Al, Cu, Sn, Ni, Au, Ag, or other suitable material withoptional adhesion and barrier layers containing titanium (Ti), titaniumtungsten (TiW), titanium nitride (TiN), tantalum (Ta), or tantalumnitride (TaN). The deposition of conductive layer 130 uses PVD, CVD,electrolytic plating, or electroless plating process. Conductive layer130 operates as ground plane, as well as an electrical interconnect.

Returning to FIG. 4 a, conductive pillars or posts 138 are formed overconductive layer 130. Conductive pillars 138 can be Cu, Al, tungsten(W), Au, solder, or other suitable material. To form conductive pillars,a thick layer of photoresist, e.g., 100-200 μm, is deposited overinsulating layer 126 and conductive layer 130. The photoresist can be aliquid or a dry film. Two layers of photoresist may be applied toachieve the desired thickness. The photoresist is patterned and metal isdeposited in the patterned areas of the photoresist using PVD, CVD,electrolytic plating, or electroless plating process. The photoresist isstripped away leaving behind individual conductive pillars 138. Inanother embodiment, the conductive pillars 138 can be implemented withsolder balls or stud bumps.

FIG. 4 d shows the pre-fabricated IPD structure 121 from FIG. 3 ainverted with solder bumps 118 mounted to conductive layers 130 c, 130d, and 130 e between conductive pillars 138. IPD structure 121 isself-aligning during solder reflow for high registration. Asemiconductor device 140 is mounted to conductive layer 130 a-130 busing electrical connections 142, e.g., solder bumps, metal bonding, orconductive paste. Semiconductor device 140 can be a passive circuitcomponent, such as a large-value capacitor (>1 nanofarad), or basebanddigital circuit, such as digital signal processor (DSP), memory, orother signal processing circuit. Note that a top surface of conductivepillar 138 and IPD structure 121 have about the same height.Alternatively, if conductive pillar 138 and IPD structure 121 havedifferent heights, then IPD structure 121 is typically made higher. Inother embodiments, conductive pillars 138 are higher than IPD structure121.

An encapsulant or molding compound 144 is deposited over the IPDstructure, between conductive pillars 138, and around semiconductordevice 140 using a printing, compressive molding, transfer molding,liquid encapsulant molding, or other suitable applicator. Encapsulant144 extends to a top surface of conductive pillars 138. Encapsulant 144can be epoxy resin, epoxy acrylate, polymer, or polymer compositematerial. Encapsulant 144 is non-conductive and environmentally protectsthe semiconductor device from external elements and contaminants.Encapsulant 144 has a coefficient of thermal expansion (CTE) that isadjusted to match that of the base semiconductor material, e.g.,silicon, with a glass transition temperature (Tg) greater than 100° C.The CTE of encapsulant 144 can be adjusted using a filler such as apowder, fiber, or cloth additive. A suitable encapsulant material isgenerally characterized by low-shrinkage, high-resistivity of greaterthan 1.0 kohm-cm, low-dielectric constant of less than 4, and low-losstangent of less than 0.05 in 500 MHz to 30 GHz range. Encapsulant 144undergoes grinding or etch-back to expose conductive pillars 138.

In FIG. 4 e, an insulating layer 146 is formed over conductive pillars138, encapsulant 144, and IPD structure 121. In one embodiment,insulating layer 146 is a passivation layer of SiO2, Si3N4, SiON, Ta2O5,ZrO2, Al2O3, polyimide, BCB, PBO, or other material having suitableinsulating properties. The insulating layer 146 is patterned or blanketdeposited using PVD, CVD, printing, spin coating, sintering, or thermaloxidation. A portion of insulating layer 146 is removed using an etchingprocess to expose conductive pillars 138.

An electrically conductive layer 150 is formed over insulating layer 146and conductive pillars 138 using a patterning and deposition process toform individual portions or sections 150 a-150 e. The individualportions of conductive layer 150 can be electrically common orelectrically isolated depending on the connectivity of the individualsemiconductor die formed on carrier 122. Accordingly, conductive layer150 constitutes an interconnect structure. Conductive layer 150 can beAl, Cu, Sn, Ni, Au, Ag, or other suitable material. The deposition ofconductive layer 150 uses PVD, CVD, electrolytic plating, or electrolessplating process. Conductive layer 150 a and 150 e electrically connectto conductive pillars 138. Conductive layer 150 provides EMI and RFIprotection for IPD structure 121, as well as package interconnection.

An insulating layer 152 is formed over insulating layer 146 andconductive layer. The insulating layer 152 can be Si3N4, SiO2, SiON,Ta2O5, ZnO, ZrO2, Al2O3, or other suitable insulating material. Theinsulating layer 152 is patterned or blanket deposited using PVD, CVD,printing, spin coating, sintering, or thermal oxidation.

A semiconductor device 154 is mounted to conductive layer 150 b-150 cusing electrical connections 156, e.g., solder bumps, metal bonding, orconductive paste. Semiconductor device 154 is typically mounted on asystem-in-package (SiP) module in a printed circuit board (PCB) assemblyafter singulation. Semiconductor device 154 can be a passive circuitcomponent, such as a large-value capacitor (>1 nF), or baseband digitalcircuit, such as DSP, memory, or other signal processing circuit.Semiconductor devices 140 and 154 can be integrated on the same deviceas thin film IPD structure 121 to save package area.

FIG. 5 shows the semiconductor device following removal of sacrificialcarrier 122 by mechanical back grinding, CMP, wet etching, or dryetching. Passivation 124 is used as a hard mark or etch stop to openadhesion layer 132 and barrier layer 134 and expose conductive layer 130for wetting. A portion of passivation layer 124 is removed to exposeconductive layer 130. Alternatively, passivation layer 124 can beblanket-etched with good selectivity to passivation layer 126. Theadhesion layer and barrier layer in 130 are later etched with goodselectivity on passivation layer 126. Conductive layer 130 b, 130 d, and130 e operate as under bump metallization (UBM).

An electrically conductive solder material is deposited over conductivelayer 130 b, 130 d, and 130 e using an evaporation, electrolyticplating, electroless plating, ball drop, or screen printing process. Thesolder material can be any metal or electrically conductive material,e.g., Sn, Ni, Au, Ag, Pb, Bi, and alloys thereof, with an optional fluxmaterial. The solder material is reflowed by heating the material aboveits melting point to form spherical balls or bumps 158. Solder bumps 158represent one type of interconnect structure that can be formed onconductive layer 130. The interconnect structure can also use bondwires, 3D interconnects, conductive paste, or other electricalinterconnect.

Accordingly, conductive pillars 138 provide electrical interconnectvertically between the passive circuit elements contained in IPDstructure 121 and other semiconductor layers and devices within thepackage. The passive circuit elements contained in IPD structure 121electrically connect through conductive pillars 138 and conductive layer130 to semiconductor device 140, as well as other external devicesthrough solder bumps 158. Likewise, the passive circuit elementscontained in IPD structure 121 electrically connect through conductivepillars 138 and conductive layers 130 and 150 to semiconductor device154.

FIG. 6 shows a similar semiconductor device as FIG. 5 with anelectrically conductive layer 160 patterned and deposited overconductive layer 130 to form individual portions or sections 160 a-160d. Alternatively, the carrier can be temporary carrier, without firstand second insulation layers. The temporary carrier is released witheither thermal or ultraviolet (UV) method after the process of thesecond interconnection structure after encapsulation. The individualportions of conductive layer 160 can be electrically common orelectrically isolated depending on the connectivity of the individualsemiconductor die. Conductive layer 160 can be Al, Cu, Sn, Ni, Au, Ag,or other suitable electrically conductive material. The deposition ofconductive layer 160 uses PVD, CVD, electrolytic plating, or electrolessplating process. Conductive layer 160 operates as ground plane, as wellas an electrical interconnect.

An insulating layer 162 is formed over conductive layer 160. Theinsulating layer 162 can be SiO2, Si3N4, SiON, Ta2O5, Al2O3, or othermaterial having suitable insulating properties. The deposition ofpassivation layer 162 may involve spin coating, PVD, CVD, printing,sintering, or thermal oxidation. A portion of insulating layer 162 isremoved to expose conductive layers 160 b, 160 c, and 160 d.

An electrically conductive solder material is deposited over conductivelayer 160 b, 160 c, and 160 d using an evaporation, electrolyticplating, electroless plating, ball drop, or screen printing process. Thesolder material can be any metal or electrically conductive material,e.g., Sn, Ni, Au, Ag, Pb, Bi, and alloys thereof, with an optional fluxmaterial. The solder material is reflowed by heating the material aboveits melting point to form spherical balls or bumps 164. Solder bumps 164represent one type of interconnect structure that can be formed onconductive layer 160. The interconnect structure can also use bondwires, 3D interconnects, conductive paste, or other electricalinterconnect.

The conductive pillars 138 provide electrical interconnect verticallybetween the passive circuit elements contained in IPD structure 121 andother semiconductor layers and devices within the package. The passivecircuit elements contained in IPD structure 121 electrically connectthrough conductive pillars 138 and conductive layers 130 and 160 tosemiconductor device 140, as well as other external devices throughsolder bumps 164. Likewise, the passive circuit elements contained inIPD structure 121 electrically connect through conductive pillars 138and conductive layers 130 and 150 to semiconductor device 154.

In FIG. 7, conductive pillars or posts 170 are formed over a sacrificialor temporary carrier similar to conductive pillars 138 in FIG. 4 a.Next, a pre-fabricated IPD structure 172, similar to FIG. 3 a butwithout solder bumps 118, is inverted and mounted to the sacrificialcarrier between conductive pillars 170 with die attach adhesive. Asemiconductor device 174 is also mounted to the sacrificial carrier withdie attach adhesive. Semiconductor device 174 can be a passive circuitcomponent, such as a capacitor, or baseband digital circuit, such asDSP, memory, or other signal processing circuit.

An encapsulant or molding compound 176 is deposited over the IPDstructure, between conductive pillars 170, and around semiconductordevice 174 using a printing, compressive molding, transfer molding,liquid encapsulant molding, or other suitable applicator. Encapsulant176 extends to a top surface of conductive pillars 170. Encapsulant 176can be epoxy resin, epoxy acrylate, polymer, or polymer compositematerial. Encapsulant 176 is non-conductive and environmentally protectsthe semiconductor device from external elements and contaminants.Encapsulant 176 undergoes grinding or etch-back to expose conductivepillars 170.

An insulating layer 178 is formed over conductive pillars 170,encapsulant 176, and IPD structure 172. In one embodiment, insulatinglayer 178 is a passivation layer of SiO2, Si3N4, SiON, Ta2O5, ZrO2,Al2O3, polyimide, BCB, PBO, or other material having suitable insulatingproperties. The insulating layer 178 is patterned or blanket depositedusing PVD, CVD, printing, spin coating, sintering, or thermal oxidation.A portion of insulating layer 178 is removed using an etching process toexpose conductive pillars 170.

An electrically conductive layer 180 is formed over insulating layer 178and conductive pillars 170 using a patterning and deposition process toform individual portions or sections 180 a-180 e. The individualportions of conductive layer 180 can be electrically common orelectrically isolated depending on the connectivity of the individualsemiconductor die. Accordingly, conductive layer 180 constitutes aninterconnect structure. Conductive layer 180 can be Al, Cu, Sn, Ni, Au,Ag, or other suitable material. The deposition of conductive layer 180uses PVD, CVD, electrolytic plating, or electroless plating process.Conductive layer 180 b and 180 e electrically connect to conductivepillars 170. Conductive layer 180 provides EMI and RFI protection forIPD structure 172, as well as package interconnection.

An insulating layer 182 is formed over insulating layer 178 andconductive layer 180 using a patterning and deposition process.Alternatively, insulating layer 182 can be blanket deposited with anypatterning. The insulating layer 182 can be epoxy matrix polymer, Si3N4,SiO2, SiON, Ta2O5, ZnO, ZrO2, Al2O3, or other suitable insulatingmaterial. The insulating layer 182 is patterned or blanket depositedusing PVD, CVD, printing, spin coating, sintering, or thermal oxidation.

The sacrificial or temporary carrier is removed by mechanical backgrinding, CMP, wet etching, dry etching, or thermal/light releasingprocess. Die attach adhesive is removed by typical wet solvent orthermal/UV light releasing together with mechanical peeling assisted bypeeling tape. An electrically conductive layer 184 is patterned anddeposited over encapsulant 176, IPD structure 172, conductive pillars170, and semiconductor device 174 to form individual portions orsections 184 a-184 d. The individual portions of conductive layer 184can be electrically common or electrically isolated depending on theconnectivity of the individual semiconductor die. Accordingly,conductive layer 184 constitutes an interconnect structure. Conductivelayer 184 can be Al, Cu, Sn, Ni, Au, Ag, or other suitable electricallyconductive material. The deposition of conductive layer 184 uses PVD,CVD, electrolytic plating, or electroless plating process. Conductivelayer 184 operates as ground plane, as well as an electricalinterconnect.

An insulating layer 186 is formed over conductive layer 184. Theinsulating layer 186 can be SiO2, Si3N4, SiON, Ta2O5, Al2O3, polyimide,BCB, PBO, or other material having suitable insulating properties. Thedeposition of passivation layer 186 may involve spin coating, PVD, CVD,printing, sintering, or thermal oxidation. A portion of insulating layer186 is removed to expose conductive layers 184 b, 184 c, and 184 d.

An electrically conductive solder material is deposited over conductivelayer 184 b, 184 c, and 184 d using an evaporation, electrolyticplating, electroless plating, ball drop, or screen printing process. Thesolder material can be any metal or electrically conductive material,e.g., Sn, Ni, Au, Ag, Pb, Bi, and alloys thereof, with an optional fluxmaterial. The solder material is reflowed by heating the material aboveits melting point to form spherical balls or bumps 188. Solder bumps 188represent one type of interconnect structure that can be formed onconductive layer 184. The interconnect structure can also use bondwires, 3D interconnects, conductive paste, or other electricalinterconnect.

Accordingly, conductive pillars 170 provide electrical interconnectvertically between the passive circuit elements contained in IPDstructure 172 and other semiconductor layers and devices within thepackage. The passive circuit elements contained in IPD structure 172electrically connect through conductive pillars 170 and conductive layer184 to semiconductor device 174, as well as other external devicesthrough solder bumps 188.

FIG. 8 illustrates two stacked semiconductor packages, similar to thedevices shown in FIG. 7. Conductive pillars 170 provide verticalelectrical interconnect between the passive circuit elements containedin IPD structure 172 and other semiconductor layers and devices withinthe package. The passive circuit elements contained in IPD structure 172electrically connect through conductive pillars 170 and conductive layer184 to semiconductor device 174, as well as stacked devices throughsolder bumps 188.

FIG. 9 has similar features as the device shown in FIG. 7 with theaddition of insulating layer 190 formed over conductive pillars 170,encapsulant 176, and IPD structure 172. In one embodiment, insulatinglayer 190 is a passivation layer of SiO2, Si3N4, SiON, Ta2O5, ZrO2,Al2O3, polyimide, BCB, PBO, or other material having suitable insulatingproperties. The insulating layer 190 is patterned or blanket depositedusing PVD, CVD, printing, spin coating, sintering, or thermal oxidation.A portion of insulating layer 190 is removed using an etching process toexpose conductive pillars 170.

An electrically conductive layer 192 is formed over insulating layer 190and conductive pillars 170 using a patterning and deposition process toform individual portions or sections 192 a-192 e. The individualportions of conductive layer 192 can be electrically common orelectrically isolated depending on the connectivity of the individualsemiconductor die. Accordingly, conductive layer 192 constitutes aninterconnect structure. Conductive layer 192 can be Al, Cu, Sn, Ni, Au,Ag, or other suitable material. The deposition of conductive layer 192uses PVD, CVD, electrolytic plating, or electroless plating process.Conductive layer 192 b and 192 e electrically connect to conductivepillars 170. Conductive layer 192 provides EMI and RFI protection forIPD structure 172, as well as package interconnection.

An insulating layer 194 is formed over conductive layer 192. Theinsulating layer 194 can be SiO2, Si3N4, SiON, Ta2O5, Al2O3, polyimide,BCB, PBO, or other material having suitable insulating properties. Thedeposition of passivation layer 194 may involve spin coating, PVD, CVD,printing, sintering, or thermal oxidation. A portion of insulating layer194 is removed to expose conductive layers 192 b, 192 c, 192 d, and 192e.

An electrically conductive solder material is deposited over conductivelayer 192 b, 192 c, and 192 d using an evaporation, electrolyticplating, electroless plating, ball drop, or screen printing process. Thesolder material can be any metal or electrically conductive material,e.g., Sn, Ni, Au, Ag, Pb, Bi, and alloys thereof, with an optional fluxmaterial. The solder material is reflowed by heating the material aboveits melting point to form spherical balls or bumps 196. Solder bumps 196represent one type of interconnect structure that can be formed onconductive layer 192. The interconnect structure can also use bondwires, 3D interconnects, conductive paste, or other electricalinterconnect.

A semiconductor device 198 is mounted to conductive layer 192 d-192 eusing electrical connections 199, e.g., solder bumps, metal bonding, orconductive paste. Semiconductor device 198 can be a passive circuitcomponent, such as a large-value capacitor, or baseband digital circuit,such as DSP, memory, or other signal processing circuit.

Accordingly, conductive pillars 170 provide electrical interconnectvertically between the passive circuit elements contained in IPDstructure 172 and other semiconductor layers and devices within thepackage. The passive circuit elements contained in IPD structure 172electrically connect through conductive pillars 170 and conductive layer192 to semiconductor devices 174 and 198, as well as other externaldevices through solder bumps 196.

FIG. 10 shows a similar semiconductor device as FIG. 5 with aninsulating layer 200 formed over conductive pillars 138, encapsulant144, and IPD structure 121. In one embodiment, insulating layer 200 is apassivation layer formed with SiO2, Si3N4, SiON, Ta2O5, ZrO2, Al2O3,polyimide, BCB, PBO, or other material having suitable insulatingproperties. The insulating layer 200 is patterned or blanket depositedusing PVD, CVD, printing, spin coating, sintering, or thermal oxidation.A portion of insulating layer 200 is removed using an etching process toexpose conductive pillars 138.

An electrically conductive layer 202 is formed over insulating layer 200and conductive pillars 138 using a patterning and deposition process toform individual portions or sections 202 a-202 d. The individualportions of conductive layer 202 can be electrically common orelectrically isolated depending on the connectivity of the individualsemiconductor die. Accordingly, conductive layer 202 constitutes aninterconnect structure. Conductive layer 202 can be Al, Cu, Sn, Ni, Au,Ag, or other suitable material. The deposition of conductive layer 202uses PVD, CVD, electrolytic plating, or electroless plating process.Conductive layer 202 b and 202 d electrically connect to conductivepillars 138. Conductive layer 202 a-202 e operates as an inductor withthe layer wound or coiled in plan-view to produce or exhibit the desiredinductive properties.

An insulating layer 204 is formed over insulating layer 200 andconductive layer 202 using a patterning and deposition process. Theinsulating layer 204 can be epoxy matrix polymer, Si3N4, SiO2, SiON,Ta2O5, ZnO, ZrO2, Al2O3, or other suitable insulating material. Theinsulating layer 204 is patterned or blanket deposited using PVD, CVD,printing, spin coating, sintering, or thermal oxidation.

An electrically conductive layer 206 is formed over insulating layer 126using a patterning and deposition process to form individual portions orsections 206 a-206 e. Conductive layer 206 can be Al, Cu, Sn, Ni, Au,Ag, or other suitable material. The deposition of conductive layer 206uses PVD, CVD, electrolytic plating, or electroless plating process.Conductive layer 206 a-206 e operates as an inductor with the layerwound or coiled in plan-view to produce or exhibit the desired inductiveproperties.

An insulating layer 208 is formed over insulating layer 126 andconductive layer 206 using a patterning and deposition process. Theinsulating layer 208 can be Si3N4, SiO2, SiON, Ta2O5, ZnO, ZrO2, Al2O3,or other suitable insulating material. The insulating layer 208 ispatterned or blanket deposited using PVD, CVD, printing, spin coating,sintering, or thermal oxidation.

Conductive pillars 138 provide electrical interconnect verticallybetween the passive circuit elements contained in IPD structure 121 andother semiconductor layers and devices within the package. The passivecircuit elements contained in IPD structure 121 electrically connectthrough conductive pillars 138 and conductive layer 130 to semiconductordevice 140, as well as other external devices through solder bumps 158.Likewise, the passive circuit elements contained in IPD structure 121electrically connect through conductive pillars 138 to the inductorformed by conductive layer 202.

FIG. 11 shows a semiconductor device similar to the device of FIG. 5with package interconnect provided only on the front side of thepackage. An insulating layer 210 is formed over conductive pillars 138,encapsulant 144, and IPD structure 121. In one embodiment, insulatinglayer 210 is a passivation layer formed with SiO2, Si3N4, SiON, Ta2O5,ZrO2, Al2O3, polyimide, BCB, PBO, or other material having suitableinsulating properties. The insulating layer 210 is patterned or blanketdeposited using PVD, CVD, printing, spin coating, sintering, or thermaloxidation. A portion of insulating layer 210 is removed using an etchingprocess to expose conductive pillars 138.

An electrically conductive layer 212 is formed over insulating layer 210and conductive pillars 138 using a patterning and deposition process toform individual portions or sections 212 a-212 e. The individualportions of conductive layer 212 can be electrically common orelectrically isolated depending on the connectivity of the individualsemiconductor die. Accordingly, conductive layer 212 constitutes aninterconnect structure. Conductive layer 212 can be Al, Cu, Sn, Ni, Au,Ag, or other suitable material. The deposition of conductive layer 212uses PVD, CVD, electrolytic plating, or electroless plating process.Conductive layer 212 a and 212 e electrically connect to conductivepillars 138. Conductive layer 212 provides EMI and RFI protection forIPD structure 121, as well as package interconnection.

An insulating layer 214 is formed over insulating layer 210 andconductive layer 212 using a patterning and deposition process. Theinsulating layer 214 can be epoxy matrix polymer, Si3N4, SiO2, SiON,Ta2O5, ZnO, ZrO2, Al2O3, or other suitable insulating material. Theinsulating layer 214 is patterned or blanket deposited using PVD, CVD,printing, spin coating, sintering, or thermal oxidation.

A semiconductor device 216 is mounted to conductive layer 212 b-212 cusing electrical connections 218, e.g., solder bumps, metal bonding, orconductive paste. Semiconductor device 212 can be a passive circuitcomponent, such as a capacitor, or baseband digital circuit, such asDSP, memory, or other signal processing circuit.

An electrically conductive solder material is deposited over conductivelayer 212 a, 212 d, and 212 e using an evaporation, electrolyticplating, electroless plating, ball drop, or screen printing process. Thesolder material can be any metal or electrically conductive material,e.g., Sn, Ni, Au, Ag, Pb, Bi, and alloys thereof, with an optional fluxmaterial. The solder material is reflowed by heating the material aboveits melting point to form spherical balls or bumps 220. Solder bumps 220represent one type of interconnect structure that can be formed onconductive layer 212. The interconnect structure can also use bondwires, 3D interconnects, conductive paste, or other electricalinterconnect.

Accordingly, conductive pillars 138 provide electrical interconnectvertically between the passive circuit elements contained in IPDstructure 121 and other semiconductor layers and devices within thepackage. The passive circuit elements contained in IPD structure 121electrically connect through conductive pillars 138 and conductive layer212 to semiconductor device 216, as well as other external devicesthrough solder bumps 220.

While one or more embodiments of the present invention have beenillustrated in detail, the skilled artisan will appreciate thatmodifications and adaptations to those embodiments may be made withoutdeparting from the scope of the present invention as set forth in thefollowing claims.

1. A method of manufacturing a semiconductor device, comprising:providing a prefabricated integrated passive device (IPD) by, forming ametal-insulator-metal capacitor over a first substrate, forming aninductor as a wound conductive layer over the first substrate, andforming a resistor over the first substrate; providing a sacrificialsubstrate; forming a first insulation layer over the sacrificialsubstrate; forming a first conductive layer over the first insulatinglayer; forming a plurality of conductive pillars over the firstconductive layer and directly connected to the first conductive layer;after forming the conductive pillars, mounting the prefabricated IPD tothe first conductive layer such that the prefabricated IPD is disposedbetween the conductive pillars, the prefabricated IPD being self-alignedto the first conductive layer; mounting a discrete capacitor having avalue greater than one nanofarad over the first conductive layer, thediscrete capacitor being electrically connected to one of the conductivepillars; forming an encapsulant around the prefabricated IPD, discretecapacitor, and conductive pillars; forming a second insulation layerover the encapsulant; forming a second conductive layer over the secondinsulating layer, the second conductive layer being electricallyconnected to the conductive pillars; and removing the sacrificialsubstrate.
 2. The method of claim 1, further including: forming a thirdinsulation layer over the second conductive layer and second insulatinglayer; and mounting a semiconductor device over third insulating layer,the semiconductor device being electrically connected to the secondconductive layer and conductive pillars.
 3. The method of claim 2,wherein the semiconductor device includes a passive device or digitalcircuit.
 4. The method of claim 1, wherein the first or secondconductive layer includes an inductor.
 5. The method of claim 1, furtherincluding forming an interconnect structure over the first insulatinglayer, the interconnect structure being electrically connected to thefirst conductive layer and conductive pillars.
 6. The method of claim 1,further including: stacking a plurality of the semiconductor devices;and electrically interconnecting the stacked semiconductor devicesthrough the conductive pillars.
 7. A method of manufacturing asemiconductor device, comprising: providing a prefabricated integratedpassive device (IPD) by, forming a metal-insulator-metal capacitor overa first substrate, and forming an inductor as a wound conductive layerover the first substrate; providing a temporary substrate; forming afirst conductive layer over the temporary substrate; forming a pluralityof conductive pillars over the first conductive layer directlycontacting the first conductive layer; after forming the conductivepillars, mounting the prefabricated IPD to the first conductive layersuch that the prefabricated IPD is disposed between the conductivepillars, the prefabricated IPD being self-aligned to the firstconductive layer; mounting a discrete capacitor over the firstconductive layer, the discrete capacitor being electrically connected toone of the conductive pillars; forming an encapsulant around theprefabricated IPD, discrete capacitor, and conductive pillars; forming afirst insulation layer over the encapsulant and conductive pillars;forming a second conductive layer over the first insulating layer, thesecond conductive layer being electrically connected to the conductivepillars; and removing the temporary substrate.
 8. The method of claim 7,further including: forming a third conductive layer over the firstconductive layer; and forming a second insulation layer over the thirdconductive layer.
 9. The method of claim 7, wherein the first or secondconductive layer includes an inductor.
 10. The method of claim 7,further including mounting a semiconductor device over the secondconductive layer, the semiconductor device being electrically connectedto the conductive pillars.
 11. The method of claim 7, further includingforming an interconnect structure over the first conductive layer, theinterconnect structure being electrically connected to the conductivepillars.
 12. The method of claim 7, further including: stacking aplurality of the semiconductor devices; and electrically interconnectingthe stacked semiconductor devices through the conductive pillars. 13.The method of claim 7, further including forming a second insulatinglayer between the first insulating layer and prefabricated IPD.
 14. Amethod of manufacturing a semiconductor device, comprising: providing aprefabricated integrated passive device (IPD) by forming ametal-insulator-metal capacitor or an inductor as a wound conductivelayer over a substrate; providing a first interconnect structure;forming a plurality of conductive pillars over the first interconnectstructure, the conductive pillars directly contacting the firstinterconnect structure; mounting a discrete capacitor over the firstinterconnect structure, the discrete capacitor being electricallyconnected to one of the conductive pillars; after forming the conductivepillars, mounting the prefabricated IPD to the first interconnectstructure between the conductive pillars, the prefabricated IPD beingself-aligned to the first interconnect structure; and forming anencapsulant around the prefabricated IPD and conductive pillars.
 15. Themethod of claim 14, further including: forming a second interconnectstructure over the encapsulant; and mounting a semiconductor device overthe second interconnect structure.
 16. The method of claim 15, whereinthe first or second interconnect structure includes an inductor.
 17. Themethod of claim 14, further including: stacking a plurality of thesemiconductor devices; and electrically interconnecting the stackedsemiconductor devices through the conductive pillars.
 18. A method ofmanufacturing a semiconductor device, comprising: forming a firstinterconnect structure; attaching a plurality of conductive pillarsdirectly to the first interconnect structure; after attaching theconductive pillars to the first interconnect structure, mounting aprefabricated integrated passive device (IPD) to the first interconnectstructure between the conductive pillars, the prefabricated IPD beingself-aligned to the first interconnect structure; and mounting adiscrete capacitor over the first interconnect structure, the discretecapacitor being electrically connected to one of the conductive pillars.19. The method of claim 18, further including: forming a secondinterconnect structure over the encapsulant; and mounting asemiconductor device over the second interconnect structure.
 20. Themethod of claim 19, wherein the first or second interconnect structureincludes an inductor.
 21. The method of claim 18, further including:stacking a plurality of the semiconductor devices; and electricallyinterconnecting the stacked semiconductor devices through the conductivepillars.